Simultaneously with the active pursuit of laboratory research much statistical work has been devoted to establishing the broad Statistics of cancer. facts of the prevalence and incidence of cancer on a firm basis. The point of most general interest is the apparently steady increase of the disease in all countries possessing fairly trustworthy records. It will be sufficient to give the figures for England and Wales as an example.
Annual Death-rates from Cancer to a Million Living.
England and Wales.
| 1871-1875. | 1876-1880. | 1881-1885. | 1886-1890. | 1891-1895. | 1896-1900. | 1901-1904. |
| 445 | 493 | 547 | 631 | 711 | 800 | 861 |
In forty years the recorded rate had risen from 403 to 861. The question how far these and similar statistics represent a real increase cannot be satisfactorily resolved, because it is impossible to ascertain how much of the apparent increase is due to more accurate diagnosis and improved registration. Some of it is certainly due to those causes, so that the recorded figures cannot be taken to represent the facts as they stand. At the same time it is certain that some increase has taken place in consequence of the increased average length of life; a larger proportion of persons now reach the ages at which cancer is most frequent. Increase due to this fact, though it is a real increase, does not indicate that the cause of cancer is more rife or more potent; it only means that the condition of the population in regard to age is more favourable to its activity. On the whole it seems probable that, when allowance has been made for this factor and for errors due to improved registration, a real increase due to other causes has taken place, though it is not so great as the recorded statistics would indicate.
The long-established conclusions concerning the incidence of the disease in regard to age and sex have been confirmed and rendered more precise by modern statistics. Cancer is a disease of old age; the incidence at the ages of sixty-five to seventy-five is ten times greater than at the ages thirty-five to forty-five. This fact is the source of frequent fallacies when different countries or districts and different periods are compared with each other, unless account is taken of the differences in age and constitution. With regard to sex females are far more liable than males; the respective death-rates per million living for England and Wales in 1904 were—males 740; females 1006. But the two rates show a tendency to approximate; the increase shown over a series of years has been considerably more rapid among males than among females. One result of more careful examination of statistics has been to discredit, though perhaps somewhat hastily, certain observations regarding the prevalence of cancer in special districts and special houses. On the other hand the fuller statistics now available concerning the relative frequency of cancer in the several organs and parts of the body, of which some account is given above, go to confirm the old observation that cancer commonly begins at the seat of some local irritation. By far the most frequent seats of disease are the uterus and breast in women and the digestive tract in both sexes, and these are all particularly subject to such irritation. With regard to the influence of heredity the trend of modern research is to minimize or deny its importance in cancer, as in phthisis, and to explain family histories by other considerations. At most heredity is only thought to confer a predisposition.
The only “cure” for cancer remains removal by operation; but improved methods of diagnosis enable this to be done in many cases at an earlier stage of the disease than formerly; and modern methods of surgery permit not Treatment. only of operation in parts of the body formerly inaccessible, but also more complete removal of the affected tissues. Numerous forms of treatment by modern therapeutic means, both internal and external, have been advocated and tried; but they are all of an experimental nature and have failed to meet with general acceptance. One of the most recent is treatment by trypsin, a pancreatic ferment. This has been suggested by Dr John Beard of Edinburgh in conformity with the theory, mentioned above, that failure of the pancreatic secretions is the cause of cancer. It has been claimed that the drug exercises a favourable influence in conjunction with operation and even without it. The experience of different observers with regard to results is contradictory; but clinical investigations conducted at Middlesex hospital in a number of cases of undoubted cancer in strict accordance with Dr Beard’s directions, and summarized by Dr Walter Ball and Dr Fairfield Thomas in the Sixth Report from the Cancer Research Laboratories (Archives of Middlesex Hospital, vol. ix.) in May 1907, resulted in the conclusion “that the course of cancer, considered both as a disease and as a morbid process, is unaltered by the administration of trypsin and amylopsin.” The same conclusion has been reached after similar trials at the cancer hospital. Another experimental method of treatment which has attracted much attention is application of the X-rays. The results vary in a capricious and inexplicable manner; in some cases marked benefit has followed, in others the disease has been as markedly aggravated. Until more is known both of cancer and of X-rays, their use must be considered not only experimental but risky.
(A. Sl.)
CANCRIN, FRANZ LUDWIG VON (1738-1812), German mineralogist and metallurgist, was born on the 21st of February 1738, at Breitenbach, Hesse-Darmstadt. In 1764 he entered the service of the landgrave of Hesse-Darmstadt at Hanau, becoming professor of mathematics at the military academy, head of the civil engineering department of the state, director of the theatre and (1774) of the mint. A work on the copper mines of Hesse (1767) earned him a European reputation, and in 1783 he accepted from Catherine II. of Russia the directorship of the famous Staraya salt-works, living thenceforth in Russia. In 1798 he became a councillor of state at St Petersburg. He published many works on mineralogy and metallurgy, of which the most important, the Grundzüge der Berg- und Salzwerkskunde (13 vols., Frankfort, 1773-1791), has been translated into several languages. His son, Count Georg von Cancrin, or Kankrin (1774-1845), was the eminent Russian minister of finance.